Species Differences of Bakuchiol-induced Liver Injury in Mice Based on Transcriptomics / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo explore the differences in response to bakuchiol-induced hepatotoxicity between Institute of Cancer Research （ICR） mice and Kunming （KM） mice. MethodThe objective manifestations of bakuchiol-induced hepatotoxicity in mice were confirmed by acute and subacute toxicity animal experiments， and enrichment pathways of differential genes between normal ICR mice and KM mice were compared by transcriptomics. The real-time quantitative polymerase chain reaction （real-time qPCR） assay was used to verify the mRNA expression of key genes in the related pathways to confirm the species differences of bakuchiol-induced liver injury. ResultIn the subacute toxicity experiment， compared with the normal mice， the ICR mice showed increased serum content of alkaline phosphatase （ALP）， and 5′-nucleotidase （5′-NT）， without significant difference， and no manifest change was observed in KM mice. Pathological results showed that hepatocyte hypertrophy was the main pathological feature in ICR mice and hepatocyte steatosis in KM mice. In the acute toxicity experiment， KM mice showed erect hair， mental malaise， and near-death 3 days after administration. The levels of serum alanine aminotransferase （ALT） and aspartate aminotransferase （AST） in KM mice （400 mg·kg-1） significantly increased（P<0.01）， and the activity of total reactive oxygen species （SOD） in liver significantly decreased（P<0.01）compared with those in normal mice， while the serum content of 5′-NT and cholinesterase （CHE） in ICR mice （400 mg·kg-1） were significantly elevated （P<0.01）. The liver/brain ratio in ICR mice increased by 20.34% and that in KM mice increased by 29.14% （P<0.01）. The main pathological manifestation of the liver in ICR mice was hepatocyte hypertrophy， while those in KM mice were focal inflammation， hepatocyte hypertrophy， and hepatocyte steatosis. Kyoto Encyclopedia of Genes and Genomes（KEGG）and Reactome pathway enrichment analyses showed that the differential gene expression between ICR mice and KM mice was mainly involved in oxidative phosphorylation， bile secretion， bile acid and bile salts synthesis， and metabolism pathway. CYP7A1 was up-regulated in all groups with drug intervention （P<0.01） and MRP2 was reduced in all groups with drug intervention of KM mice （P<0.01） and elevated in all groups with drug intervention of ICR mice （P<0.01） compared with those in the normal group. The expression of BSEP was lowered in ICR mice with acute liver injury （400 mg·kg-1） （P<0.05）. SHP1 was highly expressed in KM mice with acute liver injury （400 mg·kg-1）. The expression of FXR was diminished in ICR mice with subacute liver injury （200 mg·kg-1） （P<0.01）. SOD1， CAT， and NFR2 significantly decreased in KM mice with acute liver injury （400 mg·kg-1）， and CAT dwindled in KM mice with subacute liver injury （200 mg·kg-1） （P<0.01）. GSTA1 and GPX1 significantly increased in KM mice with acute liver injury （400 mg·kg-1） （P<0.01） and SOD1， CAT， NRF2， and GSTA1 significantly increased in ICR mice with subacute liver injury （200 mg·kg-1） （P<0.01）. CAT and NRF2 significantly increased in ICR mice with acute liver injury （400 mg·kg-1） （P<0.01）. ConclusionWith the increase in the dosage of bakuchiol， the liver injury induced by oxidative stress in KM mice was gradually aggravated， and ICR mice showed stronger antioxidant capacity. The comparison of responses to bakuchiol-induced hepatotoxicity between ICR mice and KM mice reveals that ICR mice are more suitable for the investigation of the mechanisms related to bile secretion and bile acid metabolism in the research on bakuchiol-induced hepatotoxicity in mice. KM mice are more prone to liver injury caused by oxidative stress.